Principal Investigator/Program Director (Last, first, middle): Rongo, Christopher, Gabriel RESEARCH &RELATED Other Project Information 1. * Are Human Subjects Involved? m Yes l No 1.a. If YES to Human Subjects Is the IRB review Pending? m Yes m No IRB Approval Date: Exemption Number: 1 2 3 4 5 6 Human Subject Assurance Number 2. * Are Vertebrate Animals Used? m Yes l No 2.a. If YES to Vertebrate Animals Is the IACUC review Pending? m Yes m No IACUC Approval Date: Animal Welfare Assurance Number 3. * Is proprietary/privileged information m Yes l No included in the application? 4.a.* Does this project have an actual or potential impact on m Yes l No the environment? 4.b. If yes, please explain: 4.c. If this project has an actual or potential impact on the environment, has an exemption been authorized or an environmental assessment (EA) or environmental impact statement (EIS) been performed? m Yes m No 4.d. If yes, please explain: 5.a.* Does this project involve activities outside the U.S. or m Yes l No partnership with International Collaborators? 5.b. If yes, identify countries: 5.c. Optional Explanation: 6. * Project Summary/Abstract 4286-PROJECT_SUMMARY.pdf Mime Type: application/pdf 7. * Project Narrative 946-PROJECT_NARRATIVE.pdf Mime Type: application/pdf 8. Bibliography &References Cited 4973-LITERATURE.pdf Mime Type: application/pdf 9. Facilities &Other Resources 6250-FACILITIES_OTHER_RESOURCEMSi.mpdef Type: application/pdf 10. Equipment 8215-EQUIPMENT.pdf Mime Type: application/pdf 11. Other Attachments 2814-Biosketch_Others.pdf Mime Type: application/pdf Tracking Number: Other Information Page 5 OMB Number: 4040-0001 Expiration Date: 04/30/2008 Principal Investigator/Program Director (Last, first, middle): Rongo, Christopher, Gabriel PROJECT SUMMARY. Neurons regulate synaptic activity by regulating the differentiation of the postsynaptic face of the synapse, including the amount of glutamate receptors that reach the postsynaptic surface. Do changes in glutamate receptor trafficking underlie behavioral plasticity, learning, and memory in the intact animal? The signaling molecules that regulate glutamate receptor localization need to be completely elucidated to address this question. C. elegans has been an excellent model system for studying glutamate receptors in vivo. The glutamate receptor subunit GLR-1 is required for glutamatergic signaling, and is localized to postsynaptic clusters between C. elegans neurons in a mechanosensory circuit. Using forward genetic screens, we have identified multiple genes that regulate the trafficking of GLR-1 to and from the synapse. One of these genes encodes a PDZ domain protein with orthologs in mammals, and mutations in this gene result in the failure of glutamatergic synapses to recover from habituation. Another of these genes encodes an ubiquitin ligase, and mutations in this gene result in the failure of GLR-1 receptors to be removed from the synapse. We propose three aims for understanding the role of these genes in regulating glutamatergic synapses in response to behavior. First, we will characterize changes in GLR-1 trafficking during habituation and recovery of the mechanosensory circuit. Second, we will characterize the molecular and cell biological function of the ubiquitin ligase with regard to its role in downregulating GLR-1 after habituation. Third, we will characterize the molecular and cell biological function of our PDZ domain protein with regard to its role in upregulating GLR-1 after recovery from habituation. The molecular and cell biological function of these new genes will provide clues to the mechanisms by which glutamate receptors are regulated. Project Description Page 6